In his main work, The World as Will and Representation, first published in 1819, Schopenhauer presents his philosophy as a whole and systematically.

In the appendix of the work, which is included in the third volume of the Greek edition, he thoroughly confronts primarily the theoretical philosophy of Kant (the Critique of Pure Reason), and secondarily the other parts of the Kantian system (ethics and philosophy of law, aesthetics, and philosophical teleology). This critical confrontation, as expressly noted by Schopenhauer himself, constitutes an organic part of his philosophical "system" (in a certain sense, an introduction to it), and understanding it is a necessary condition for a substantive comprehension of the whole.

The World as Will and Representation is undoubtedly among the great classical works of European philosophy. The appendix with the critique of Kant, due to its depth, thoroughness, and systematic nature, is a text whose study proves beneficial for both the student of Schopenhauer's philosophy and for that of Kant's theoretical philosophy.